Answer:
Domain = { (0,2), (3,3), (1,0) }
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Step-by-step explanation:
The rule f(x,y) = (x+1,y-1) says to add 1 to the x coordinate and subtract 1 from the y coordinate. So let's say the input point is (7,2). This would move it to (8,1).
Now let's say that you accidentally erased the "(7,2)", but you still have the "(8,1)". You'd have to work through the steps backwards to get back to (7,2)
So you'll effectively use this rule g(x,y) = (x-1, y+1) which is the inverse transformation. Whatever f(x,y) does, the g(x,y) function will undo it and go opposite. We'll subtract 1 from the x coordinate and add 1 to the y coordinate.
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So that's what we'll do with the set of points { (1,1), (4,2), (2,-1) }
We have (1,1) become (0,2) after applying the g(x,y) rule
(4,2) becomes (3,3) after using g(x,y)
(2,-1) becomes (1,0) after using g(x,y)
Therefore, the domain is { (0,2), (3,3), (1,0) }
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The mapping diagram is shown below.